<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			.d1{
				width: 0;
				height: 0;
				border-width: 100px;
				border-style: solid;
				border-color: transparent #0099CC transparent transparent;
				/* transform: rotate(90deg); */ /*顺时针旋转90°*/ 
			}
		</style>
	</head>
	<body>
		<div class="d1"></div>
	</body>
</html>
